This disclosure relates to methods of servicing a wellbore. More specifically, it relates to servicing a wellbore with particulate material compositions.
Natural resources (e.g., oil or gas) residing in the subterranean formation may be recovered by driving resources from the formation into a wellbore using, for example, a pressure gradient that exists between the formation and the wellbore, the force of gravity, displacement of the resources from the formation using a pump or the force of another fluid injected into the well or an adjacent well. The production of fluid in the formation may be increased by hydraulically fracturing the formation. That is, a treatment fluid (e.g., a fracturing fluid, a gravel packing fluid, etc.) may be pumped down the wellbore at a rate and a pressure sufficient to form fractures that extend into the formation, providing additional pathways through which the oil or gas can flow to the well.
Treatment fluids used in fracturing operations generally comprise polymers and crosslinkers (e.g., a cross-linked gel system) that are used for increasing the viscosity of the fluid such that particulate materials can be suspended in the fluid. These treatment fluids may have a complex set of ingredients and may require specialized conditions, such as for example specific pH values and the use of pH buffering agents.
Oftentimes, after the treatment fluid has performed its intended task, it may be desirable to reduce its viscosity (e.g., “break” the fluid or gel) so that the treatment fluid can be recovered from the formation and/or particulate material may be dropped out of the treatment fluid at a desired location within the formation. Breakers can be generally employed to reduce the viscosity of treatment fluids. Unfortunately, traditional breakers may result in an incomplete and/or premature viscosity reduction. Premature viscosity reduction is undesirable as it may lead to, inter alia, particulate material settling out of the fluid in an undesirable location and/or at an undesirable time. Alternately, encapsulated breakers may be used to control the release rate of breaker. However, such option adds to material costs. Thus an ongoing need exists for improved compositions and methods of using treatment fluids comprising particulate materials.